Duplicating apparatus



Bec. 3i, 1935. J. HERNLUND 25,089

DUPLICATING APPARATUS Filed Aug. 13, 1934 2 Sheets-Sheet 1 fFQnj.

Dec. 31, 1935. A W HERNLUD 2,026,089

DUPLICATING APPARATUS J2 dem jlorzreys Patented Dec. 31, 1935 UNITED STATES DUPLICATING APPARATUS John W. Hernlund, La Grange, Ill., assigner to Ditto, Incorporated, Chicago, Ill., a corporation of West Virginia.

Application August 13, 1934, Serial No. 739,596

2 claims.

The invention relates to duplicating apparatus and has for one of its objects the provision of a compact duplicating device which will be simple in construction and relatively inexpensive to manufacture.

One form of the invention is embodied in a .duplicating device of the hectograph type.

port it on any suitable object such as a stand,

atable, or the equivalent. One end of the sheet metal platen or bed member is provided with integral tongues or lugs engageable with pockets formed in a reenforcing strip which is secured to one end of a heotograph band. The other end of the hectograph band is provided with a reenforcing strip of similar construction and the pockets of the latter strip are engageable by spring-pressed bars mounted beneath the platen or bed member, the construction being such that the spring-pressed bars draw the hectograph band taut over the platen.

The means provided for attaching the hectograph band to the platen and for drawing it taut upon the platen is simple in construction and are constructed so that the hectograph band may be positioned upon the platen in its correct position with very little effort on the part of the operator.

Other advantages will become apparent as the following detailed description progresses, reference being had to the accompanying drawings, Wherein- Fig` 1 is a plan view of a duplicating device which embodies the invention.

Fig. 2 is a longitudinal section taken on line 2 2 of Fig. 1.

Fig. 3 is a transverse section taken on line 3 3 of Fig. l. Y

Fig. 4 is an enlarged fragmentary section taken on line 4 4 of Fig. 1.

Fig. 5 is a bottom plan view of the hectograph band shown in Fig. 1.

Fig. 6 is an enlarged fragmentary section taken on line 6 6 of Fig. 5, and

Fig. 'I is an enlarged fragmentary section taken on line 'I 'I of Fig. 1.

Referring to the drawings wherein a preferred embodiment of the invention is illustrated, the reference character I0 designates generally a platen or bed member which is formed, preferably, from sheet metal. The member IIJ oomprises a flat platen II provided with integral downward extending side flanges I2, the side (Cl. lOl-131) .1.

flanges I2 being provided with inwardly extending apertured lugs I3 in which rubber bumpers I5 are mounted (Fig. 4). The rubber bumpers I5 are adapted to support the improved dupliv eating device upon a stand, a table or any other '5 suitable support.

At one end, the platen EI is provided with spaced tongues or lugs Ii which are formed by cutting notches I3 in the platen II. These tongues or lugs I'I have their outer ends cut olf so that they do not project beyond the end of the platen Ei. It will be noted that the platen II is curved downwardly as at 2U between the lugs I'I and between the lugs ii and the side 4 flanges I2. 'Ihis construction enables the oper- 15- ator to register, without any diiculty, one end of a hectograph band, hereinafter described, with the tongues or lugs I'I.

The other end of the platen II is alsocurved downwardly as designated by the reference character 22. This end of the platen il is provided with notches 25 alined with the tongues or lugs I'I. Also alined with the tongues or lugs I'I are fingers or bars 26 which are slidably journaled beneath the platen II by transverselyvextending 25 bars 21 and 28. The bars 21 and 28 may be secured to the underside of the platen II in any suitable manner such as, for instance, spot welding.

As best shown in Fig. 4, the inner end of each 30 bar 26 is provided with an integral downwardly extending lug 30. A spring 3I is provided for each bar 26 and has one of its ends secured to the associated lug 36, the other end of the spring 3I being secured to Aa. pin 32 projecting down- 3 wardly from the associated bar 23. It will be noted that the springs 3| urge the bars 26 outwardly to the right (Figs. 1, 2 and 4).

Between the bars 26 is an angle iron member 35 rigidly secured to the under surface of the platen II..

Drawn taut over the platen II is a hectograph band which is designated generally by the reierence character 36. It comprises a backing member 31 and a coating of gelatin 38. The 45' backing member may be made of paper, fabric or any other suitable material. Clamped to the ends of the paper backing 37 are reenforcing members 39 and 46 which are preferably formed from sheet metal and are preferably identical in 50 construction so that the ends of the band 36 are interchangeable. In other words, either end of the hectograph band 36 may be associated with either end of the platen II.

The construction of the reenforcing members 39 and 40 is best illustrated in Figs. 4 to 7, inclusive. It will be noted that each of the reenforcing members is bent to provide a U-shaped portion 42 clamped upon one end of the backing member which is folded to provide a tongue 43 projecting into the associated U-shaped por-v tion 42. The ends of the backing member 31 are also clamped between the U-shaped portions 42 and tongues 44 which engage the bottom surface of the backing member 37. The tongues 44 are bent intermediate their ends to provide pockets 46 which will register with the lugs I1 and the bars 26 when the hectograph band or pad S6 is secured to the platen Il in the manner illustrated in Figs. l, 2, 4, 6 and 7. It will be noted that the pockets 46 co-operate with the lugs I1 and the bars 26.to aline the side edges of the hectograph pad 3S with the side edges of the platen Il. Y

When the hectograph pad 36 is to be secured to the vplaten Il, the pockets 4G at one end of the hectograph pad are alined, preferably, with the outer ends of the bars 2S and then the operator grasps the angle member 35 and employing it for leverage, displaces the reenforcing member 4&3 to the left (Figs. 1 and 2) against the action of the springs 3| so that the pockets 46 in the reenforcing member 39 may be engaged with the lugs l1. The operator then releases the reenforcing member 40 and the springs 3i yieldingly urge the reenforcing member to the right (Figs. l and 2) until the hectograph pad 36 is drawn taut over the platen Il. The hectograph pad may then be moistened and employed in the usual manner.- Preferably, a rubber roller is utilized to press the masters and copy sheets against the duplicating surface of the hectograph pad. It will be noted that the curved upper surfaces of the ends of the platen Il and the side edges of the notches formed therein guide the reenforcing members into alinement with the lugs I1 and the bars 26.

I claim:

1. Hectograph apparatus comprising a platen, lugs projecting from one end of said platen, said 5 end of said platen being curved downwardly intermediate said lugs, the other end of said platen being provided with notches alined with said lugs, said other end of said platen being curved downwardly intermediate said notches, springpressed bars alined with said notches, and a hectograph band, and reenforcing members on the ends of said band, said reenforcing members being provided with pockets engageable by said lugs and said spring-pressed bars to hold said band taut over said platen, said curved ends of said platen serving as guides to bring said pockets into positions wherein they are engageable by said lugs and said spring-pressed bars.

2. Hectograph apparatus comprising a platen having a plurality of pairs of notches in one end thereof, a lug projecting from said end of said platen between the notches of each pair thereof, said end of said platen being curved downwardly between and at .either side of said lugs, the other end of said platen being provided with notches alined with said lugs, said other end of said platen being curved downwardly, spring-pressed bars alined with the last-mentioned notches, and a hectograph band, and reenforcing members on the ends of said band, said reenforcing members being provided with pockets engageable by said lugs and said spring-pressed bars to hold said band taut over said platen, said curved ends of said platen serving as guides to bring said pockets into positions wherein they register with said lugs and said spring-pressed bars.

JOHN W. HERNLUND. o 

